The present invention relates generally to the air entering a turbomachine; and more particularly to a system for sampling the airstream entering the inlet system.
Some turbomachines, such as, but not limiting of, gas turbines, and aero-derivatives, have an air inlet system that channels the incoming airstream towards a compressor. The inlet system usually has a filter section, which screens the airstream of foreign objects and other undesired materials. Typically, the inlet system and the compressor are created out of metals that may corrode due to the environment (ambient conditions, etc) in which the turbomachine operates. Industry standards provide techniques for monitoring the corrosive rate of an environment.
These turbomachines may develop microenvironments related to the ambient conditions in which the turbomachine operates. These microenvironments, which have accelerated airflows and pressures, typically increase the corrosion rate of the components of the compressor. Therefore, to accurately determine the corrosion rate, one should not simply measure the ambient conditions and make a conclusion on the airstream and the microenvironment. The airstream downstream of the filter section should be monitored to determine the environmental effects of the airstream on the compressor components.
One method of determining the corrosion rate in the microenvironment is to place strips (hereinafter “coupons”) in the airstream. Overtime, the coupons become corroded and fail. A user monitors the coupons and a time to failure. The coupons may be sent to a lab to determine the type(s) or corrosives that caused the failure.
There are a few concerns with the described method of determining the corrosion rate. A coupon within the inlet system may corrode, dislodge, and become a projectile within the inlet, potentially causing damage to the compressor components. Additionally, placing the coupons in the inlet channel may create flow distortion waves, which can also damage turbomachine components.
For the foregoing reasons, there is a need for a system that measures the corrosives within an airstream flowing in an inlet system. The system should monitor the corrosion rate of the inlet system. The system should not create distortion waves when used.